The present invention generally relates to the field of internal combustion engines, and more specifically to a coalescing filter assembly to remove oil aerosol from vent gas within the crankcase of the internal combustion engine.
Modern internal combustion engines including both diesel and gasoline engines are frequently provided with a ventilation system for venting air circulating within the crankcase of the engine. After an air-fuel mixture is drawn into the combustion chamber of the internal combustion engine, the mixture is ignited and burned until it is discharged into the atmosphere. However, not all of the air-fuel mixture is completely burned and discharged. During the operation of the engine, small amounts of hot combustion gases leak past the piston rings and through the oil circulating within the crankcase to create a pressurized mixture of air, exhaust gases and atomized oil. The leaked gas is commonly referred to as blow-by gas. If left unvented, the blow-by gas may cause a number of problems. First, the blow-by gas may deteriorate the quality of the lubricating oil present in the crankcase. Additionally the blow-by gas tends to increase the pressure in the crankcase and cause leaking of the lubricating oil. Therefore, a mechanism is required for removing blow-by gas from the crankcase.
In an effort to minimize environmental harm, it is preferable not to discharge air from within the crankcase directly to the atmosphere. Instead some means of removing oil entrained by the blow-by gas is utilized prior to venting to the atmosphere. Prior art air-oil coalescers include features such as elaborate labyrinth like designs and/or various filtration media. The filter media is often subject to clogging. Concerns for such systems include the possibility of over pressurization that may occur if the venting and/or filtering path becomes clogged or otherwise has an insufficient rate of removal of the gas from the crankcase interior.
Thus, a need remains for further contributions in this area of technology. The present invention satisfies this need in a novel and non-obvious fashion.
One form of the present invention contemplates an air-oil coalescer for a gas in a crankcase of an engine, comprising: a first housing element having a substantially radial surface and a substantially axial surface, the radial surface coupled to a member within the crankcase that rotates about an axis; a second housing element having an outlet port, the second housing element adjoining the first housing element; a filter positioned within a cavity defined between the first housing element and the second housing element; and, wherein at least one of the first housing element and the second housing element includes a plurality of inlet ports, said filter positioned within the cavity such that the gas entering the inlet ports passes through at least a portion of the filter before exiting the outlet port.
Another form of the present invention contemplates: an air-oil coalescer for a vent gas in a crankcase of an engine, comprising: a filter; a housing having an at least partially hollow interior in fluid communication with the crankcase through at least one inlet opening, the housing also including an outlet opening; a rotating component within the crankcase; and, wherein the housing is concentrically mounted to the rotating component to synchronously rotate therewith about an axis, the at least one inlet port of the housing facing substantially radially from the axis, the filter being positioned within the housing so that the vent gas entering the interior of the housing through the at least one inlet opening must pass through the filter to reach the outlet opening.
Yet another form of the present invention contemplates an apparatus, comprising: a housing including a plurality of inlet ports and at least one outlet port; a filter positioned within the housing so that a fluid entering the inlet ports must pass through the filter to reach the outlet port; a cover including an outlet conduit having an intake opening and an exhaust opening, the intake opening being in fluid communication with the outlet port of the housing, the outlet conduit also being in fluid communication with an aperture, the aperture being in fluid communication with a fluid at atmospheric pressure; a diaphragm positioned within the outlet conduit; a spring positioned within the cover to bias the diaphragm toward the aperture; and, the diaphragm being movable within the cover from a first position wherein the outlet port of the housing is in fluid communication with the exhaust opening of the outlet conduit to a second position wherein the outlet port of the housing is not in fluid communication with the exhaust opening of the outlet conduit, and wherein the diaphragm is configured such that the fluid from the aperture exerts a force to move the diaphragm toward the second position and the fluid from the outlet port of the housing and the spring exert forces to move the diaphragm toward the first position.
One object of the present invention is to provide a unique air-oil coalescer.
Related objects and advantages of the present invention will be apparent from the following description.